Here, we developed a statistical test based on a haplotype statistic, H12, capable of detecting both hard and soft sweeps with similar power. We used H12 to identify multiple genomic regions that have undergone recent and strong adaptation using a population sample of fully sequenced Drosophila melanogaster strains (DGRP). We then developed a second statistical test based on a statistic H2/H1 | H12, to test whether a given selective sweep detected by H12 is hard or soft. Surprisingly, when applying the test based on H2/H1 | H12 to the top 50 most extreme H12 candidates in the DGRP data, we reject the hard sweep hypothesis in every case.

Here we uncovered a dramatic example of clonal interference between multiple similar mutations occurring at the same locus within replicate populations of Methylobacterium extorquens AM1. … Despite conferring a large selective benefit, the majority of these alleles rose and then fell in frequency due to other lineages emerging that were more fit.

In the blogosphere

How reliable (or, well, consistent) are the species descriptions in field guides?

New to Tim: Stephen Jay Gould may have fudged the numbers on his exposé of number-fudging in The Mismeasure of Man.

There is a Tumblr of beautiful scientific illustrations, because of course there is.